1. Field of the Invention
This invention relates primarily to torque conversion (power transmission), and more specifically, this invention relates to a torque converter utilizing homopolar machines having segmented magnets for excitation.
2. Description of the Prior Art
There are many applications that require light weight, variable speed drives. For example, a constant torque, variable speed drive could be utilized in conjunction with a ship propeller having a fixed pitch to replace a controllable pitch propeller.
Prior art devices have utilized homopolar generator and motor arrangements to provide torque conversion, as illustrated by U.S. Pat. No. 1,507,825-- Gill et al.; U.S. Pat. No. 2,979,630-- Bishop et al.; U.S. Pat. No. 3,163,792-- Sayers; and U.S. Pat. No. 3,383,532-- Zeisler et al. All of these patents relate to arrangements in which homopolar machines are located on a common axis and are interrelated to perform a torque conversion function. In U.S. Pat. No. 2,408,080-- Lloyd, there are disclosed various types of structures utilizing homopolar machines for the transmission of power. In FIG. 3 of this patent there is illustrated a structure in which the homopolar machines are concentric, with one having a smaller radial dimension than the other so that it fits into the other.
Although the prior art does not seem to teach the utilization of a plurality of excitation magnets for each of the homopolar machines in a torque converter, such a plurality of excitation magnets (segmented magnets) have been suggested for use with homopolar machines. Examples of such structures may be found in U.S. Pat. No. 339,772-- Hering and in the Morse patents, U.S. Pat. Nos. 1,271,061; 1,327,349; and 1,327,350.
None of these prior art arrangements poses a very desirable solution to the problems involved in interconnecting the homopolar machines and of eliminating the conductors outside the device. As a result, these devices are relatively large and heavy and yet permit the utilization of only relatively small currents. In addition, the efficiencies of these devices are relatively low.